FIG. 1 is a conventional one hand held probe for measuring the signals on each lead of electronic circuit packages and other electronic components mounted on a substrate (these are collectively referred to as "DUT" below). Probe 10 has alligator clip 12, which is coupled to a portion adjacent to a tip section 11 of the probe via cable 13. By means of this type of probe, one of the leads (for instance, the ground terminal) is clasped and anchored by alligator clip 12 and tip section 11 is brought into contact with another lead. This type of probe is advantageous in that it is possible to keep one lead electrically connected to alligator clip 12, and therefore the user can quickly introduce tip section 11 to several leads in succession, using one hand.
However, it is often impossible to use such a probe to clasp narrow-pitch leads of an electronic circuit package as well as the leads of electronic components mounted on a substrate at high density, therefor such probes can not perform their function in this case.
FIG. 2 shows another conventional probe 20. This probe 20 has sub-tip section 22 next to main tip section 21. This sub-tip section 22 is attached to the side near the main tip section 21 pivotally on its pivot so that it moves within a plane that includes the axis of the main tip section and the axis of the sub-tip section. Thus, the pointed end of this sub-tip section 22 can move up to and away from the pointed tip of main tip section 21. This structure is suitable for probing leads with a relatively narrow pitch using one hand.
When a probe is used to measure RF signals, coaxial structure must be typically maintained in its axial position that is as close to the measuring point as possible. Therefore, the length of exposed main tip section 21 must be as short as possible in order to maintain this coaxial structure. With a design of short main chip section 21, however, when trying to move sub-tip section 22 closer to main tip section 21, sub-chip section 22 bumps against outer surface 23 of the probe before it gets close to main tip section 21, resulting in that they cannot get close proximity each other. On the other hand, if the main tip section 21 is made longer to prevent the sub-tip section 22 from bumping against the outside surface 23, in turn, a problem with the coaxial structure will occur. That is, this type of probe is designed taking into consideration whether it is more important to maintain a coaxial structure or to have a pitch that makes narrower pitch probing possible, and the designer must inevitably choose between these two alternatives. The pitch which enables this type of probe to be used for probing is limited to approximately 5 mm, therefor this type of probe is not suitable for probing leads that have a narrower pitch than that.
Furthermore, the position of the sub-tip section often changes slightly as the force applied by the user changes during probing, because the end section of the type of probe shown in FIG. 2 is not rigid. Consequently, it is often the case that the measurements are unstable and do not have good reproducibility when this probe is used for measuring microcurrent and high-frequency signals.
Consequently, the purpose of the present invention is to present a one hand held probe for probing electronic circuit packages and various electronic components with a pitch that is narrower than the minimum pitch of leads with which the probes of prior art can cover.
Another purpose of the present invention is to present a probe for measuring signals that is flexible so that it can be adjusted by the user to any pitch as needed.
Yet another purpose of the present invention is to present a probe for measuring signals with high measurement stability and reproducibility.